The answering machine owned by Steven is a digital machine. It does not use a tape to record messages. Therefore, when Steven hits the "skip" button, you should not hear the tape fast forwarding, because there isn't one. Also, you should not hear the tape clicking on a new message.
The satellite dish Chip falls into is pointing straight up. Satellite dishes track satellites in geosynchronous orbit, which must orbit at the equator. For the satellite dish to be pointing straight up, it must be on the equator.
The odds that Steven would have been in jail (the prison scene) for "receiving stolen property" are slim to none, and after an interview Steven would have likely been cited at the police station and given a court date. Some states have a separate but similar charge called "possessing stolen property" or "possession of stolen property." The distinguishing factor here is when the accused learned the goods were stolen. If he knew at the time he acquired the property, then it is receipt of stolen property. It is possession of stolen property if he only learned the property was stolen after he obtained it. All Steven had to do was tell the police who Chip Douglas really was, and Steven would have been sent home and it would have been The Cable Guy who would have been arrested.
There is no "switch" than turns on and off the cable reception, as depicted in the hallway of Steven's apartment. For the cable to have gone out like that, the cable would to have been disconnected completely. The switch that "Chip" turns on and says "All set!" is most like the switch for the 4th floor hallway lights at the apartment building where Steven lived.
Steven and Rick (Steven's "Rock" friend) act as if computers and search engines did not exist, having to resort to a research department to find "Chip Douglas" which could have easily been done with the search engines that existed at the time the movie was made: Lycos (1994), Alta Vista (1995), Excite (1993), Ask Jeeves (Ask), Infoseek (1994), Inktomi (1996), WebCrawler (1994).
During the basketball game at the gym, after Chip shatters the backboard, he falls down into the glass on the floor. However you can clearly see an outline within the shattered glass, where he should land.
In the bathroom scene when Chip Douglas is beating up Ray (Owen Wilson) he throws him onto the hand dryer while it's on and makes him suck on it showing his face blowing up. When Ray takes his mouth off there was clearly no air coming out to begin with because his hair is standing still while he is standing in front of it.
The angle of the video of Steven and Robin on the couch is different than the camera angle that chip placed in Steven's apartment; as it was positioned, only the bottom half of the couch would have been in the field of view.
In the end, Chip is hanging from a tower holding on to arm of the main character near the dish. He falls down and lands in the exact middle of the dish. In more distant shots, the tower is nowhere near the dish.
When Steven returns to the office to find the desktop "movie" that the Cable Guy made showing Steven and Robin talking about Hal, Hal sees a different version of them on the couch than the original scene, right before Steven and Robin watched Sleepless in Seattle.
Steven grabs Chip after having jumped, which would be a thrust several times Chip's own weight, and then holds him with only one arm for more than a minute, a feat that not even the strongest man could achieve.
At the very end of the movie when "Chip" is being taken away in the helicopter, we can clearly see the final scenes are at night, yet the upward shots of the paramedic reveal a blue screen in the helicopter's roof windows.